MOLECULAR PHYLOGENY OF THE TRIBE HEDYSAREAE WITH SPECIAL REFERENCE TO ONOBRYCHIS (FABACEAE) AS INFERRED FROM nrDNA ITS SEQUENCES

A total of 53 species (54 sequence accessions) representing 28 species of the tribe Hedysareae, 5 species of Vicioid clade and 19 species of Galegeae including the two Glycyrrhiza species as outgroups was included in a phylogenetic analysis using nrDNA ITS sequences with maximum parsimony method. The analysis, based on successive reweighting by rescaled consistency index, revealed that Vicioid clade is the first branch followed by Chesneya-Caragana clade and Astragalean clade as successive sisters to Hedysaroid clade. The genus Alhagi is well allied, as the basal most taxon, with the remainder of Hedysaroid clade. Ebenus and Taverniera are each monophyletic and weakly allied taxa. Hedysarum is not monophyletic, its species are dispersed across Hedysaroid clade. Sulla a segregate of Hedysarum, forms a well supported monophyletic group with the inclusion of H. humile. The enigmatic genus Eversmannia is allied with Onobrychis clade. Onobrychis itself is not monophyletic due to inclusion of the two Hedysarum species, and Onobrychis subgenus Onobrychis is not monophyletic as well, whereas Onobrychis subgenus Sisyrosema forms a strongly supported clade. In contrast to Onobrychis section Heliobrychis, sections Dendrobrychis and Onobrychis appear not to be each monophyletic. Hedysareae is circumscribed herein to include only Alhagi, Ebenus, Eversmannia, Hedysarum, Onobrychis, Sulla, Taverniera, Coretrodendron and Sartoria.